

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Notification</title>
    <link rel="stylesheet" href="index.css">
</head>
<body>
<div class="container">
    <h1>Notifications API</h1>
    <button id="btn">测试</button>
</div>
<script src="index.js"></script>
</body>
</html>